CZ200370A3 - Eye for reinforcing peripheral region around the hole in a strap and device for fitting the eye to the strap - Google Patents

Abstract

The invention relates to a ringless eyelet ( 10 ') comprising a plate ( 11 ) arranged on the display side ( 23 ) of the carrier strip ( 20 ), and a tube-shaped collar penetrating the hole in the carrier strip. The hem of the collar of the eyelet element ( 10 ') is supported on the rear side ( 24 ) of the carrier strip ( 20 ). The aim of the invention is to connect the eyelet to the carrier strip ( 20 ) faster and in a more cost-effective manner. In order to achieve this, the free end part of the collar of the eyelet element ( 10 ') is provided with projections ( 16 ). An essentially closed ring profile ( 50 ), into which the collar projections ( 16 ) are integrated, is created when the collar is hemmed. After hemming, pressure points ( 40 ) are created on the carrier strip ( 20 ) between the collar projections ( 16 ) and the abutment surfaces ( 49 ) formed by the plate ( 11 ), said pressure points reliably holding the carrier strip ( 20 ). Said carrier strip ( 20 ) extends namely inside ( 51 ) the ring profile ( 50 ) beyond the pressure points ( 40 ). An eyelet is obtained using only one.

Description

Eyelet to reinforce the edge area around the opening in the strap and a device for attaching the eyelet to the strap

Technical field

BACKGROUND OF THE INVENTION The present invention relates to an eyelet for reinforcing a peripheral region around a strap opening comprising a plate for attaching to the visible side of the strap, a tubular neck with a through hole and an arcuate transition between the plate and the neck. eyelets in the final state, resting on the back of the strap. The invention further relates to a device for attaching the eyelet to the strap.

BACKGROUND OF THE INVENTION

One-piece and two-piece guides are known.

In the known one-piece stitches of the aforementioned type (US-PS 2,901,800, FIG. 5), the stitch is formed by a single component consisting of a plate and a short neck. On the front side of the neck there are teeth formed at a radial distance, forming a collar on the neck. The alignment of this eyelet is carried out by means of an additional element in the form of a sleeve which can also form part of the rivet press. The teeth bend and not the neck of the eye are bent with respect to the plate on which the perforated material is located. After fastening the eyelet, the additional element is removed and can be reused. The fastening of the eyelet attached to the fabric is not satisfactory, because only the unique teeth are involved. The bent teeth cannot prevent the pulling movement of the fabric at the eye-reinforced opening, because the peaks of the teeth point in the direction of such pulling movement.

There are one - piece guides of another type (DIN 7333) which

they do not have collars that surround the neck end. These guides are used essentially for inflexible straps, such as cardboard. Until now, it has not been possible to use flexible straps such as tarpaulins. The cardboard had to be punched before the known one-piece stitches were fitted, which was lengthy and time consuming. After putting on, the eyelet with its plate rests on the visible side, passes through its neck through a pre-cut hole in the cardboard and its L-shaped rim fits on the back of the strap.

Strap perforation is not required for two-part eyelets, which are stitches of another type, which consist of a loop section on one side of the strap and a disc section on the other side of the strap (DIN 7332). With the help of these stitches, the canvas can also be used as straps, but higher production costs and higher labor requirements are required. Indeed, both the eyelet portion and the disk portion must be made, and both parts must be placed in the respective upper and lower tool of the setting device. Production, storage and supply of two parts is more space and time consuming. In addition, the pull-out resistance is limited. If, in this known two-piece eyelet, the omission of the disc portion was to be verified and only to work with the eyelet portion, as in the prior art, the unusable pulling resistance of the eyelet mounted on the strap would be obtained.

In the two-part eyelets, which are made as so-called bushings, the annular disc portion comprises both the inner and outer edges of the individual teeth which are axially pressed against the plate of the eyelet portion while perforating the strap. These teeth bend on the visible side of the strap in the region of the plate of the loop portion. This is done on the one hand by the transition between the neck and the plate of the eye part and, on the other hand, by the type of so-called serrated ring, as used for example in

patentek. Also this loop is very expensive in production and application.

SUMMARY OF THE INVENTION

SUMMARY OF THE INVENTION The object of the present invention is to provide an inexpensive and quick-to-mount eyelet which, after being set up on the strap, is characterized by a high tensile strength. This is achieved by the measures set forth in claim 1, which are explained in the following.

By means of axial or radial protrusions at the free end of the neck, a gripping means is obtained which creates, at the annular profile forming the neck folding, special pressing points on the captured strap against which the strap is set against tensile stresses. In the annular neck roll profile, the neck end protrusions are integrated which abut on insertion of the edge region of the strap opening on the abutment surfaces which are formed by a plate or transition

The strap extends inside the annular profile through the thrust points to the edge of its opening. The tension of the strap occurs at the pressing points of the edges rolled in the interior of the annular profile with the curled edges of the perforated strip as a barrier. The eyelet according to the invention is considerably safer against pulling out compared to the prior art.

of this annular profile between the plate and the neck of the eye.

Compared to the much more expensive two-piece eyelets, the eyelets of the invention have a surprisingly high pull-out resistance, which is 30 to 75% higher. This is the case with so far critical, flexible or extensible straps that could not be fitted with a one-piece eyelet at all. Due to the one-piece design of the invention, the disc portion is saved and thus the material, storage costs, transportation costs and hand-over during slipping are saved. The one-piece eyelet of the invention allows for quick preparation, which reduces the cost of fitting the eyelet. Taking into account the annular profile during the roll-up, it is sufficient to form the neck of the eye according to the invention long enough. Naturally, the thickness of the bearing wall is also taken into account. At the free end of the neck, only axial or radial protrusions, which can be produced in different ways, are then still to be provided.

One possibility is to form protrusions, for example, by radially punching the tubular wall of the neck. When the neck is rolled up, these radial projections penetrate into the retained area of the rim opening where they engage and create thrust points with respect to the opposite abutment surface on the plate. From the manufacturing point of view, however, the other possibility of forming axial projections is simpler. A toothed or wavy end edge of the neck as set forth in claim 2 is suitable for this. In this case, the entire neck edge is continuously profiled and is not provided, as in the aforementioned prior art, with separate, spaced-apart projections. During profiling, according to the invention, both the neck and the projections are shaped together. When shaping the annular shape during roll-up, the tooth is embedded in the strap material and not only grips between the tooth and the abutment surface, but also the form fit between the tooth and the strap. The greater the tension exerted on the strap, the safer the tooth enters the strap. This explains the surprisingly high tensile strength of the stitch according to the invention.

The invention also relates to a device for attaching an eyelet according to the invention. Its essence is apparent from claim 10. In the known snap-on devices for attaching the eyelet to flexible straps, such as tarpaulins, displacement pins are used in the upper tool at the front of the axially movable centering insert. In this way it is possible to cut out the strap • · ·· 0 «0« 00000 during the hemming stroke of both tool parts

000000 0 0 00 · 0 larger hole to ensure trouble-free connection with the disc part. The invention goes in a completely different way.

Although no disc-shaped parts are used in the invention, as has already been said, only the eyelet is used with a device as is usual with two-piece stitches. However, on the other hand, displacement pins are not required on the middle insert of the upper tool, because according to the invention the opening in the strap is made as small as possible. This is important because, as already mentioned, when creating a substantially closed annular roll profile, an excess length of the edge region of the strap opening that extends inside the annular profile through said thrust points is required. A particularly reliable process is obtained when the pressure ring and the back pressure ring described in claim 13 are used in the apparatus. If necessary, the shaping of these pressure and counterpressure rings as set forth in the other dependent claims is also provided.

BRIEF DESCRIPTION OF THE DRAWINGS

Further measures and advantages of the invention will become apparent from the dependent claims, the following description and the drawings. In the drawings, the invention is illustrated by way of example. The drawings show:

FIGS. 1 and 2 are a cross-sectional side view of the eyelet provided with the loop according to the invention, FIG. 3 and FIG. the discs in the initial state, that is, before setting them on

5 shows an enlarged view of a portion of the peripheral region of the eyelet of the invention, designated V in FIG. 4, in a plane and FIG. 6 in axial section, the two-part eyelet preparation device shown in FIG. lower tool at the top dead center of its stroke movement.

DETAILED DESCRIPTION OF THE INVENTION

The eyelet 10, as shown in FIGS. 1 and 2, is to reinforce the edge region 21 of the aperture 22 cut into the strap 20. The strap 20 is generally of a flexible and possibly extensible material, such as a tarpaulin for trucks. According to the invention, the desired hole reinforcement is achieved with the one-piece eyelet 10. In Figures 4 and 5, the eyelet 10 is shown in its initial state prior to application. Giant. 1, 2a and 3, on the other hand, show the eyelet 10 in its final state after its application to the strap 20 to reinforce the opening 22.

The eyelet 10 can be divided into an arched, substantially radially extending plate 11 and an axially extending tubular neck 12. For reasons of better shape rigidity and the lateral annular roll-up of the neck 12, the plate 11 has an arched profile 13. The neck 12 is provided at its free end 15 with axial projections 16. These projections 16 in the present example seen in FIG. 5 form a rounded tooth tip 17. Said projections 16 have the shape described below.

· »♦ · fl fl fl fl fl fl fl fl fl fl fl fl fl fl fl fl fl fl fl fl fl fl fl fl fl fl fl fl fl fl fl fl fl fl · ·· «· ··· ·· ··

The tooth tips 17 are provided with convex curves 27, while the tooth gaps 18 have a concave curvature 28. Thus, the tooth profile 19 has a wavy course which is made asymmetrical. That is, the radius of curvature of the convex curvature 27 at the tip of the tooth 17 is smaller than the radius of the concave curvature 28 of the tooth gap 18.

This loop 10 is attached to the strap 20 in the device 30 shown in FIG. 6. The device 30 consists essentially of five axially movable parts overlapping each other. These include in the present case a stationary lower tool 32 and a passively axially movable pressure ring 34 relative thereto. The device 30 also includes an actively movable upper tool 31 with a coaxially positioned centering insert 33 with respect to the lower tool 32. with respect thereto also passively axially movable. The upper tool 31 is also closed in the circumferential area by a passively axially movable counter-pressure ring 44. The centering insert 33 as well as the counter-pressure ring 54 acts against the lower tool 32 in the direction of the silo arrows 35, 55, while the pressure ring 34 in the lower tool 32 is mirrored in the direction of the second arrow 36 against the upper tool 31. The springs 56 are formed as helical springs, with internally located pins 57 mounted on the pressure ring 34. The group consisting of the upper tool 31, the centering insert 33 and the back pressure ring 54 and the group consisting of the lower tool 32 and the pressure ring 34 are displaceable relative to one another, as shown by the third arrow 37.

The pressure ring 54 is guided on the peripheral surface 63 of the upper tool 31. The pressure ring 54 is exerted by a compression spring 64, which is supported between the face of the flange 65 of the upper tool 31 and the contact surface of the slot 66 in the pressure ring 54. Determined by the end stop. This end stop in this example consists of a head 67 of a set of guide rods 68, which can be longitudinally adjusted by means of a thread 69 and a self-locking nut 71. The head 67 is supported at rest on the upper face of the flange 65. in respect of the upper instrument.

FIG. 6 shows, as already mentioned, the top dead center of the stroke movement, when the upper tool 31 is in the maximum stroke condition relative to the lower tool 32

38. In this way, the eyelet 10 can be conveniently fitted to the abutment profile of the upper tool 31 and the centering insert 33. For this purpose, the upper tool 31 has a clamp 39 corresponding to the profile of the disc 11. The clamped area 39 is subjected to abrasion when used. To facilitate repair of the worn device 30, the lower part of the upper tool 31 is therefore provided with an insert 31 which is detachably mounted on the upper part of the upper tool 31 by means of the illustrated screw or the like. This insert 31 has a clamp

39.

After inserting the eyelet 10, the end of the neck 12 is supported on the circumferential surface of the centering insert 33. The centering insert 33 is provided with a flat end surface 43. To secure the position of the eyelet 10 in the upper tool 31 and centering insert 33 there. , which in the illustrated case consists of a radially outwardly projecting and spring-mounted pin.

A strap 20 that is not pre-punched is inserted between the two tools 31, 32. The springs 56 hold the pressure ring 34 in a defined, starting position as shown in FIG. At the maximum lifting height of the tools 31, 32, the decisive upper side 45 of the pressure ring 34 is above or preferably at the same height with the cutting edge 42 formed on the lower tool 32. This results in • A · «

A A A A A horizontal support plane 60 for the strap 20 shown in dot-dash in dotted lines 34 in FIG.

A A AAA

A A · A arrows 37 of the upper group of the centering insert 33 and the strap 20 lying over

In the third stroke direction consisting of the upper tool 31, the back pressure ring 54 enters the pressure ring 34 with a first back pressure ring 54. The two rings 34, 54 are provided with substantially parallel bevels 58 and 59 which grip the strap 20, whereby the strap 20 is first slightly stretched. The bevel 58 of the compression ring 34 is formed relative to the support plane 60 at the acute angle 61 shown in dashed dotted lines 61, which is fixed to the upper side 45 of the compression ring 34 for receiving the strap 20. The bevel 69 of the back pressure ring 54 is formed substantially. parallel to the bevel 58 of the compression ring 34. Therefore, as the two tools 31, 32 move against each other, the strap 20 extends around an edge 62 formed between the upper side 45 and the bevel 58 of the compression ring 34. This is the strap 20 in the perforated area 29 smoothly stretched. The strap 20 is therefore in the retracted position on the support plane 60.

Then, the centering insert 33 loaded with the press ram enters the upward facing side 23 of the strap 20 and pushes it against the cutting edge 42 of the lower tool 32 resting on the support rear side 24. This results in a circular opening cut out of the strap 20. In this case, the cutting radius 42 determined by the cutting edge 42 is smaller than the radius 26 of the neck 12 shown in FIG. 6.

When the upper tool 31 sinks further in the direction of the third arrow 37, the strap 20 is clamped more firmly between the two bevels 58, 59 of the rings 34, 54. In this case, the neck 12 of the eyelet 10 passes through the resulting hole into the lower tool 32 until the eyelet plate 11 contacts the compression ring 34 over the strap 20. In this movement in the direction of arrow 37 the upper tool 31 overcomes the spring force 56 of the compression ring 34 Φ φ and the neck 12 and the axial projections 16 on the bending profile 47 of the lower tool 32 are rolled up. The compression spring force 64 of the back pressure ring 54 is less than the pulling force acting on the pressure ring 34. This is because the bending profile 47 wears out after prolonged use. Then just replace the other insert 32.

Upon roll-up, the ratios particularly apparent from FIG.

3. Practically the entire length 48 of the neck 12 of the eye 10 seen in FIG. 4 is rolled up on the rear side 24 of the strap 20 into the visible annular section 50. The annular section 50 also includes projections 16 on the neck 12. By pulling on the edge region 21 of the aperture 20 in the strap 20, these projections 16 are pressed against the abutment surface 49 forming the arched profile 13 of the plate 11. The annularly located thrust points 40 are apparent here in FIG. an end zone 41 of the strap 20 is disposed to match the annular profile 50. Also during the roll-up of the end zone 41, the strap 20 is firmly gripped between the bevels 58, 59.

With the 20 defined, the tension shown in Fig. 1 occurs until the use of a loop 10 fitted to the load strap in the direction of the fourth arrow 52,

3. This tensile load is transmitted by the thrust points 40. The thrust points 40 are characterized in particular by the clamping effect between the projections 16 and the abutment surface 49. Furthermore, due to the described profiling of this projection in the form of a tooth profile 19, shaped connections are formed. The points of the tooth penetrate into the material of the strap 20, but due to the rounding 27, 28 of the tooth profile 19, no cracks occur in the strap 20. This prevents voltage concentration. It occurs in front of the tooth peaks 17 and also in the arched tooth gaps 18

On the other side of the thrust points 40, the stepped extension 53 of the thickness 20 of the strap 20 shown in FIG. 3 is because the strap 20 tends to expand again to the original thickness 25. At tensile loads of the strap 20, This increases the strength of the shaped joint and achieves a surprisingly high tensile strength of the loop 10 in the final state in which it is applied to the strap 20.

A PARTNERS i ^ OOOPfshg 2, Halkova 2

Czech Republic ····

Claims (16)

An eyelet for reinforcing an edge region (21) around an opening (22) in a strap (20), which consists of a plate (11) for fitting on the visible side (23) of the strap, a tubular neck (12) with a through hole (22) and an arcuate transition (14) between the plate (11) and the neck (12), the free end (15) of the neck (12) being provided with protrusions (16), and with the neck (12) of the eyelet (10) in its final state on the rear side (24) of the strap (20), characterized in that the projections (16) extend in the axial and / or radial direction, wherein the roll-up of the neck (12) forms a closed annular profile (50) into which the free end (15) having protrusions (16), and in intermediate alignment of the edge region (21) of the strap (20), the protrusions (16) in the annular profile (50) are pushed onto the abutment surface (49) formed by the plate (11) or arcuate transition ( 14) and form the thrust points (40) on the captured strap (20) against which the strap (20) ), when the tensile load is in the direction of the fourth arrow (52), the strap (20) extends in the interior (51) of the annular profile (50) through the thrust points (40) to the edge of its opening. Ring according to claim 1, characterized in that the axial projections (16) are formed by a tooth profile (19) formed at the end of the neck (12). Eyelet according to claim 2, characterized in that the tooth tips (17) are convexly rounded and the tooth gaps (18) are concave rounded, the two rounds (27, 28) forming a wavy profile of the tooth profile (19). A loop according to claim 3, characterized in that the wavy course of the tooth profile (19) is asymmetrical. • A AAAA 94 AA AA AAA AAA AAA AAA AAA AAA AAA AA - 13 A loop according to claim 3 or 4, characterized in that the convex curvature (27) of the tooth tips (17) are smaller than the concave curvature (28) of the tooth gaps (18). A loop according to any one of claims 1 to 5, characterized in that the strap (20) is made of a flexible and / or extensible material. A loop according to claim 6, characterized in that the strap (20) consists of a canvas. A loop according to claim 6, characterized in that the strap (20) consists of a reinforced plastic film. Eyelet according to one of claims 1 to 8, characterized in that the diameter of the opening in the strap (20) is less than the clear distance between the diagonally lying annular profiles (50) of the rolled-up neck (12). Device for attaching an eyelet (10) according to one of claims 1 to 9 on a strap (20) with a lower tool (32) having a bending profile (47) for the neck (12) of the eyelet (10) with an upper tool (31) for carrying an eyelet (10) slidably mounted relative to the lower tool (32), a strap (20) being positioned between the two tools (31, 32), characterized in that the upper tool (31) is provided with an axially movable centering the insert (33) having an end face (43) that is planar, and the lower tool (32) having an annular cutting edge (42) that interacts with the end face (43) of the centers! inserts (33) when punching the web (20) lying between them, the radius (46) of the cutting edge (42) being smaller than the outer radius (26) of the neck (12) of the eyelet (10). Device according to claim 10, characterized in that it is in the bottom 000 Apparatus according to claim 11, characterized in that the annular end surface of the helical compression spring bears against the pressure ring (34) by which the pressure ring (34) is subjected to a load. - 12 PATENT CLAIMS Device according to one of Claims 10 to 12, characterized in that a pressure ring (54) in the upper tool (31) is assigned to the pressure ring (34), the strap (20) being when moving into the rings (34, 54). direction third darts (37) clamped between the two 14. Equipment according to claim 13, characterized with both Rings (34, 54) are for clamping the strap (20) provided two bevels (58, 59) opposed to one another. - 14 tools (32) are located radially spaced from the bending profile (47) by a pressure ring (34) which is loaded with force in the direction of the second arrow (36), the pressure ring (34) being located at the maximum stroke of both tools (31). 32 at a height of the cutting edge (42) of the lower tool (32) and forms a support plane (60) for the strap (20) positioned between the two tools (31, 32). Apparatus according to claim 14, characterized in that the bevel (58) of the compression ring (34) is formed at an acute angle (61) relative to the support plane (60) defined by the upper side (45) of the compression ring (34). ), wherein the bevel (59) of the back pressure ring (54) is formed parallel to the bevel (58) of the pressure ring (34). Device according to one of Claims 10 to 15, characterized in that the upper tool (31) and / or the lower tool (32) are provided with inserts (31, 32) having a clamp (39) and / or a bending profile (31). 47) for the loop (10). AVAILABLE OFFICE, ZfcAíAW ŠVORČÍK KALENSKÝ A PARTNER! 12u UQ Prague 2, Haikova 2